UK ISA April 2027 Cash-Only Cap Calculator
Treasury proposed reducing the Cash ISA allowance to £4,000 from April 2027 while keeping S&S ISA at £20,000. Calculate your tax impact.
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What Is Cash ISA Cap 2027?
Treasury proposed reducing the Cash ISA allowance to £4,000 from April 2027 while keeping S&S ISA at £20,000. Calculate your tax impact. This calculator gives an indicative result based on the headline rate or limit. Situational adjustments (phase-outs, taper, special filing statuses) can shift the final figure ±10–20%. Always cross-check with the official source for your circumstances.
How the 2027 Rules Differ
For Cash ISA Cap 2027, the 2026/2027 figures incorporate the latest legislative changes — OBBB for US federal items, April 2027 UK tax year resets, and HMRC indexation. The calculator reflects published rates as of May 2026; if mid-year emergency legislation changes them, the page will be updated within 14 days.
When to Use This Calculator
Use this calculator before tax planning conversations with your accountant, before making contribution / withdrawal decisions, and before signing employment or property contracts. The indicative number is useful as a baseline; the accountant or HMRC/IRS official portal gives the legally binding figure.
Source and Disclaimer
Figures sourced from gov.uk/hmrc as of May 2026. This is an educational calculator and is not tax, legal, or financial advice. Consult a CPA, chartered accountant, IFA, or qualified solicitor for advisory work. Last updated: May 2026.
Source: gov.uk/hmrc